How to calculate approximate traffic volume for the past 12 months in Google Keyword Tool

In my “Demand for SEO Jobs” post, I plotted keyword demand for the phrase “SEO Jobs” across 2008 based on Google keywords data. A few folks have asked me to explain how I did that, so without further ado:

How to calculate approximate traffic volume for the past 12 months in Google Keyword Tool

First of all you’re going to need the data. Go to Google’s keyword tool and select a few keywords you’re interested in.

Before you export data from the keyword tool, be sure to select “Show Search Volume Trends” in the “Choose columns to be displayed:” drop down list:

From there it’s easy to calculate the search volume of your keyword by month by using the ratio data provided in the CSV export. Let’s look at how to do it (I’ve provided a sample excel spreadsheet if you’d like to look at my calculations) in a few easy steps:

If you download the search volume trends data, you’re presented with a set of ratios that look like this:

Fortunately, Google gives you the approximate average traffic volume for the month (in my example: November). Knowing the traffic for one month makes it simple to calculate the traffic numbers for all of the others.

Just divide the search volume by the ratio you’re given for the same month, and then multiply that figure by the ratio for the month you need to calculate the traffic for. Did that make sense? Hopefully!